Photographic solution



Patented Aug. 24, 1943 UNITED STATE s PATENT OFFICE PHOTOGRAPHICSOLUTION Jersey No Drawing. Application August 3, 1939, Serial'No.288,178

Claims. (Cl. 95- -88) This invention relates to a process of decreasingthe corrosiveness of photographic solutions which may have a tendency toattack metal parts. More particularly this invention relates to improvedphotographic solutions containing dyes and a method of treating thesolution to eliminate or minimize the corrosiveness of such solutions.

In the production of various photographic materials in many instancessolutions or suspensions of the materials may be flowed, sprayed orotherwise deposited on metal surfaces. Or, in other instances thevarious solutions containing coloring material or other ingredients maybe applied in some manner to a film baseor other component ofphotographic film. It is wellknown that in some instances the solutionsare I not chemically inert but may, for example, cor-.

may not only be corroded but such corrosion' causes the formation ofsludges or slimes which may, unless care is taken, get into the productbeing fabricated.

We have found that the corrosiveness as above described, which may bepresent in certain photographic solutions, may be substantially stoppedor considerably minimized by the incorporation therewith of certainagents, which apparently improve the properties of the solution from thecorrosion standpoint without damaging the value of the solution for itsphotographic uses. Not only is it possible to use the solutions when incontact with more expensive metallic surfaces, but apparatus parts maybe made out of nickel, tin and the like, when our invention is beingemployed.

This invention has for one object to provide an improvedphotographicsolution which may be employed in contact with metallic parts withoutsubstantial attack thereof. Still another object is to provide a methodof treating corrosive photographic solutions to substantially eliminateor at least-minimize the corrosiveness thereof. Still another object isto provide improved 7 photographtic solutions containing dyes or othercoloring agents which may have a tendency to attack metallic parts, forsubstantially elimigraphic solution containing nigrosine dyes or relateddyes which may be readily applied to a I film base without any attendantdifliculty of sludge or slime incorporation. Still another object is toprovide a method of minimizing the corrosive tendencies of anilineoxidation products. Still another object is to render corrosion, when itdoes occur, more uniform and without local pitting action. Other objectswill appear hereinafter.

We have found that certain agents may be added to photographicsolutions, suspensions or the like, which may have a tendency to attackmetallic parts and such tendency substantially eliminated orconsiderably minimized. It is desired to point 'out that the solutionsmay contain various ingredients commonly encountered in photographicsolutions as for example aliphatic alcohols, gelatin, resins, organicacids, cellulosic derivatives and dyes. In particular, we have. foundthat solutionscontaining colors such as dyes which are to be applied tofilm base or other parts of the film, may be treated by our invention sothat they do not attack metal apparatus to any extent. Furthermore, thevalue of the dye containing photographic solution is not materiallyaffected for its intended use.

We have found that if a small amount of amino alcohol, alkylol amine orsubstantially equivalent compound are suitably'incorporated with thesolution, that many corrosive tendencies thereof may be minimized. Inthe case of ,of illustrating one specific application of our inventionand not to be construed as a limitation thereof. v

In accordance with this example, it was desired to apply colors from anorganic solution to a clue base and other negative bases. In particular,it was desired to apply ,a nigrosine dyecontaining solution to such filmbase. The solution in addition to the coloring agent such as nlgrosinedye may also contain organic solvents such as methanol, acetone andethanol. In the previous employment of nigrosine dye solutions, metallictanks containing the solution, the pipe lines conducting the solutionsto the treatment of the film base had suffered attack and somedifliculty had been experienced by sludges and slime formation,

We have found, however, that in accordance with the example underdescription about 1% by weight of diethylaminoethanol added to thenigrosine dye-containing photographic solution substantially reduced theattack thereof on metal parts. In the case of parts constructed ofnickel, the attack thereon was practically totally stopped. Similarremarks apply to parts constructed of stainless steel or plated withchromium, rhodium or other related metals from group four of theperiodic system.

It was further found that other amino compounds containing an alcoholgroup in the molecule function satisfactorily. However, in view of theready availability the diethylaminoethanoi was preferred.

While 1% has been described in the aforementioned example, otherproportions may be employed. The preferred proportion might depend inany specific instance, for example on the amount of thecorrosive dyepresent in the solution, the character of the metallic part to contactthe solution and related factors. If the metal part is acorrosion-resistant part such as stainless steel the quantity andcharacter of the inhibitor need not be as eiiicient as in the instancewhere the' metal part is, for example,

nickel, tin and the like.

We have found that /2%-2% or 3% usually sumces in most instances.However, it is apparent that smaller amounts may be used but theprotection is less, while greater amounts involve added expense and maybe regarded as wasteful.

We have found that our addition agents not only render corrosivephotographic solutions considerably less active in their attack oncommon metal parts such as nickel, iron and steel, but their attack onstainless steel of the 18% chromium, 8% nickel or the 24% chromium, 12%nickel type is appreciably decreased, by most'any of the group of agentswe have described herein.

Our invention possesses other advantages. Frequently when corrosiontakes place the metal surface is severely corroded in local spots,resulting in a badly pitted condition 01' the surface. This may renderthe surface unfit for use even though the over-all weight loss oi thesample is not great. It was noted in our corrosion tests that thesamples, if any corrosion had taken place, showed a very uniformcorrosion. Although the corrosion was small in practically all cases,there was definitely no tendency for local by dissimilar allwl groups,groups containing a larger number of carbon atoms, or otherwisemodified. Also, it is possible to employ primary or secondary aminoalcohols either singly or in various mixtures. Generically we refer toour materials as anti corrosion agents. As indicated above, photographicsolutions containing other dyes such as aniline blue,

Zapon colors (manufactured by General Dyestufl Corporation, New Yorkcity) etc., as well as other ingredients-such as aliphatic alcohols,halogenated hydrocarbons, cellulosic esters, resins, etc., may betreated in a comparable manner to improve them.

It is, therefore, apparent that our invention is susceptible of somemodification.

What we claim and desire to be secured by 2. An improved solution forphotographic uses 1 exhibiting a minimum of corrosiveness,anycorrosiveness being relatively uniform and without substantial pitting,containing as essential ingredientsa nigrosine dye and a small contentof diethylaminoethanol between about .5%-3%.

3. A solution for application to a photographic film base, the solutioncomprising a metal-corrosive, spirit-soluble dye, an organic solvent forthe dye, and an amino alcohol selected from the group consisting ofdialkyl amino alcohols and di-(hydroxy alkyl amino) alcohols, said aminoalcohol being present in an amount sufficient to retard corrosion of ametal when the solution is in contact with a metal. a

4. A solution for application to a photographic film base, the solutioncomprising a metal-corrosive, spirit-soluble dye, an alcoholic organicsolvent for the dye, and an amino alcohol selected from the groupconsisting of dialkyl amino alco; hols and 'di-(hydroxy alkyl amino)alcohol, said amino alcohol being present in an amount sufficient toretard corrosion of a metal when the solution is in contact with ametal.

5. A solution for application to a photographic mm base, the solutioncomprising a metal-corrosive, spirit-soluble nigrosine dye, an organicsolvent for the dye, and an amino alcohol selected from the groupconsisting of dialkyl amino alcohols and di-(hydroxy alkyl amino)alcohols, said amino alcohol being present in an amount suilicient toretard corrosion of a metal when the solution is in contact with ametal.

6. A solution for application to a photographic film base, the solutioncomprising a. metal-corrosive, spirit-soluble nigrosine dye, analcoholic organic solvent for the dye, and an amino alcohol selectedfrom the group consisting'of dialkyl amino alcohols and di-(hydroxyalkyl amino) alcohols, said amino alcohol being present in an amountsumcient to retard corrosion of a metal when the solution is in contactwith a metal.

7 A solution for application to a photographic film base, the solutioncomprising a metal-corrosive, spirit-soluble aniline blue dye, anorganic solvent for the dye, and an amino alcohol selected from thegroup consisting of dialkyl amino alcohols and di-(hydroxy alkyl amino)alcohols, said amino alcohol being present in an amount suflicient toretard corrosion 01 a metal when the solution is in contact with ametal.

8. A solution for application to a photographic film base, the solutioncomprising a metal-corrosive, spirit-soluble aniline blue dye, analcoholic organic solvent ,for the dye, and an amino alcohol selectedfrom the group consisting of dialkyl amino alcohols and di-(hydroxyalkyl amino) alcohols, said amino alcohol'being present in an amountsufiicient to retard corrosion of a'metal when the solution is incontact with a metal.

9. A solution for application to a photographic film base, the solutioncomprising a metal-corrosive, spirit-soluble dye, an organic solvent forthe dye,'and a dialkyl amino alcohol, said dialkyl amino alcohol beingpresent in an amount sufficient to retard corrosion of a metal when thesolution is in contact with a metal.

10. A solution for application to a photographic film base, the solutioncomprising a metal-corrosive, spirit-soluble dye, an alcoholic organicsolvent for the dye, and a dialkyl amino alcohol,

amount sufiicient to retard corrosion of a metal when the solution is incontact with a metal.

11. A solution for application to a. photographic film base, thesolution comprising a metal-corfilm base, the solutioncomprising ametal-corrosive, spirit-soluble nigrosinedye, an alcoholic organicsolvent for the dye, and a dialkyl amino alcohol, said dialkyl aminoalcohol being present in an amount sufllcientto retard corrosion of ametal when the solution is in contact a metal.

13. A solution for application to a photographic film base, the solutioncomprising a metal-corrosive, spirit-soluble aniline blue dye, anorganic solvent for the dye, and a dialkyl amino alcohol,

1 said dialkyl amino alcohol being present in an amount sufficient toretard corrosion of a metal when the solution is in contact with ametal.

14. A solution for application to a photographic film base, the solutioncomprising ,a metal-corerosive, spirit-soluble aniline blue'dye,-;analcoholic organic solvent for the dye, and a dialkyl amino alcohol, saiddialkyl amino alcohol being present in an amount suflicient to retardcor- ,said'dialkyl amino alcohol being present in an solution is incontact said amino alcohol being presentin an amount sufilcient toretard corrosion of a metal when the solution is in contact with ametal. GALE F. NADEAU. WILLIAM M. TUCKER.

with

